[temp mitigation][ios] add timeout to Run Build Test step (#83001)
### Description
Mitigating https://github.com/pytorch/pytorch/issues/82890. We don't want a job to hog a runner for 4 hours if it should have failed 3 hours ago. This step normally takes less than 1 minute.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/83001
Approved by: https://github.com/malfet
